TRO 



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TRO 



TXITBR'NATE, Lat. triteniatus. Having 

 three biternate leaves : a species of super- 

 decompound leaf. 



TRIT'ICCXI. Wheat. An extensive genus 

 of grasses. Triandria Digynia, Name 

 from tero, to thrash. The awned and the 

 rush-leaved wheat, and the couch-grass, 

 *re the indigenous species of this genus ; 

 but the species cultivated are the T. hyber- 

 num or winter-wheat, the T. eesticnm or 

 summer wheat, and the T. spelta or spelt. 

 See WHEAT. 



TRI'TON, ) 1. In mythology, a demi- 



TKITO'JJIA. ) sea-god, the trumpeter of 



Neptune. 2. A genus of gasteropods of 



The order Nudibranchiata, shell spiral. 



3. A genus of perennial plants. Triandria 

 Monogynia. Cape of Good Hope. 



TRI'TOJJE. In music, an interval of four 

 degrees, containing three tones between 

 the extremes. 



TEITOX'IDE, from T^/TO?, third, and ox- 

 ide. An oxide of the third degree. 



TRICM'PHAL ARCH. An architectural 

 monument in the form of an arch, erected 

 in honour and to the memory of some 

 successful commander. The archivault 

 of the Roman triumphal arch was usu- 

 ally adorned with figures of victory 

 holding palms, crowns, &c. 



TRICM'PHAL CROWN. A crown usually 



awarded by the Romans to their victori- 

 ous generals. It was first made of wreaths 

 of laurel, and afterwards of gold. 



TRIUM'VIRI (of Rome), were three men 

 who jointly obtained the sovereign power. 

 The first of these were Cssar, Crassus, 

 and Pompey. Their government was a 

 triumvirate. 



TRIV'IAL NAME. A specific name : that 

 which is added to the generic name to 

 distinguish species. 



TRO'CAR. The name of a surgical in- 

 strument used in tapping for the dropsy, 

 corrupted from French un trois quart, a 

 three quarters, in allusion to the three 

 sides from which the point is made. 



^ to run. A 



name in anatomy for two processes of the 

 thigh-bone, distinguished into the greater 

 and less. The muscles inserted into these 

 processes perform the office of running. 



TROCHE, from T^WS, a wheel. The 

 name in pharmacy for a medicine com- 

 posed of powders, made up with glutinous 

 substances into little cakes and afterwards 

 dried : troches are now called lozenges. 



TRO'CHEE, T^O/OS- A rhythmical mea- 

 sure, consisting of two syllables, a long 

 and a short. 



TRO'CHILUS, T^o^Ao?, a small bird. A 

 name applied by Linnaeus to the genus of 

 humming-birds. 



TROCHIT'ICS, from r^o;, a wheel. A 

 term in mechanics for the science of rota- 

 tory motion. 



TROCH'LEA, T6%Xt, a pulley, from 

 T6i%t, to run. In anatomy, a kind of 

 cartilaginous pulley, through which the 

 tendon of one of the muscles of the eye 

 passes. This muscle is named the mus- 

 culus trochlearis, and the nerve which, 

 serves it, the trochleator. 



TRO'CHOID, from TJO^OS, a wheel, and 

 Ei5S, like. Wheel-like. In geometry, 

 a figure which is described by a circle 

 that rolls in a straight line, with a pointer 

 pin in the circumference, on a fixed 

 plane parallel to or in the plane of the 

 moving circle. 



TROCHO'IDES, from rgo%os, a wheel, and 

 E/So5,like. A species of moveable connec- 

 tion of bones, in which one bone rotates 

 upon another. 



TRO'CHVS. The name given by Linnaeus 

 to a genus of gasteropods of the family 

 Trochoida, from trochus, a top, in allusion 

 to the conical shape of the shell. About 

 150 species are known, many of which 

 are fossil. The recent species are gene- 

 rally found near coasts. 



TROO'LODYTES, from r^oyArj, cave, and 

 duca, I enter. Men who dwell in subter- 

 raneous caverns. 



TRO'OON. The generic name given by 

 Linn to the Cauroucotii : scansorian birds 

 which build in the hollows of trees, feed 

 on insects, and live solitary in marshy 

 forests. Some part of the plumage is 

 I usually of a metallic lustre. Found in 

 both Continents. 



TROM'BONK. In music, a wind instru- 

 ment blown by the mouth, resembling in 

 form the military trumpet, of which it is 

 the base. The name implies great trumpet. 



TRO'NA. A native sesqui-carbonate of 

 soda, found at Lukena, in Africa. 



TRON'AOE. Formerly a duty paid for 

 weighing of wool. 



TROPJE'DLTM. Indian cress. A genus of 

 herbaceous plants. Octandria Monogy- 

 tuVi. NamediB. oUrtpaum, or r&rxict, 



